The present invention relates generally to an agricultural implement having a plurality of soil packer units in the form of helical coils which are positioned forward of a harrow assembly, the implement adapted for towing behind a vehicle.
Compaction of soil in the vicinity of newly planted seed has long been known to substantially increase crop yield. It is known to provide soil compaction by a number of relatively heavy packing wheels mounted on a cultivator, but this arrangement has not been completely satisfactory.
More recently, increased interest has been directed toward the concept of soil compaction by means of a series of helical coil packers extending rearwardly of associated harrow assemblies. Examples of such arrangements are shown in U.S. Pat. No. 4,418,762 and Canadian patent Nos. 838,417, 871,991, 1,081,021, 1,099,566, and 1,212,569. However, this arrangement has disadvantages in that clumps or clods of soil, weeds and other debris loosened and raised by the harrow assemblies, are pressed back into the soil by the soil packers.
Agricultural implements have also been designed with soil packer devices located forward of the harrow assemblies. One such example is the Fuerst Flexible Tine Drill Harrow manufactured by Fuerst Brothers, Inc. of Gibson City, Ill. Another is the Kewanee 80-90 Mulcher manufactured by the Kewanee Farm Equipment Co. of Kewanee, Ill.
There is also now available from Morris Rod Weeder Co., Ltd. of Yorkton, Canada, a packer/harrow implement sold under the name Morris Rangler II Packer Harrow Bar, which has a plurality of helical soil packer units directly coupled to a transversely extending, transverse frame member or tool bar. Harrow assemblies are carried behind the packer units by elongated, arched carrier arms connected directly to the frame member and extending over the soil packer units. Each of &he packer units is connected by means of short, pivotal links directly to the frame member for up and down shifting movement in substantial independence of any vertical movement of the trailing harrow sections.
A number of benefits are realized by mounting the soil packer units ahead of the harrow sections or assemblies. For example, clumps and clods of soil as well as trash and debris are left on the top of the ground, thereby functioning as a barrier to prevent moisture loss through capillary action. The clumps, clods, trash, etc., reduce wind and water erosion, and the trash cover enhances moisture intake and retention from rain, irrigation, etc. In addition, weeds pulled from the soil by the harrow tines are left on the ground surface to die, instead of being worked into the ground for additional growth as is observed with conventional soil packer/harrow apparatus.
This invention relates to an improvement in packer/harrow implements, such as the Morris implement identified above, and specifically, to an improved mounting arrangement for the soil packer coils.
In accordance with this invention, transversely oriented soil packer coils are mounted directly to a transverse frame adjacent to the rearwardly extending harrow bars which, in turn, are connected to the transversely extending frame member. In this arrangement each coil is located entirely between and substantially transverse to a pair of adjacent harrow arms.
More specifically, each coil is mounted between a respective pair of harrow arms by means of a pair of link arms which pivotally mount the coil directly to the transverse frame directly under the pair of harrow arms. The link arms of each coil are also free to pivot about the longitudinal axis of rotation of the coil so that the coil maintains uniform ground engaging contact independent of any up and down movement of the harrow arms.
Along with the attachment of the soil packer coils directly to the harrow arms, this invention also relates to the manner in which the soil packer coils are mounted for rotation about their own longitudinal axes.
In one exemplary embodiment, the link arms which mount each coil to a pair of adjacent harrow arms are provided with axially shortened stub shafts which extend toward each other, generally coincident with the longitudinal axis of the coil, and generally perpendicular to the respective link arms.
These stub shafts are receivable within apertures provided in support plates fixed at either end of the coil. In addition, the support plates have affixed thereto, on either side of the apertures, roller bearing assemblies which enable the coil to rotate freely about the otherwise non-rotatable stub shafts. In this regard, "non-rotatable" as used above describes the shaft relative to its associated link arm and its own axis. Of course, the shaft is free to rotate, along with the link arm, about the pivot mounting between the link arm and harrow arm.
In another exemplary embodiment, the stub shafts are replaced by a pair of half-shafts which extend along the longitudinal axis of the coil, and are separably joined approximately mid-way along the axis of the coil by a sleeve bushing. The half shafts are fixed at their opposite respective ends to the link arms via a conventional roll pin arrangement which precludes rotation relative to the link arm, but which permits pivotal movement with the link arm about the pivotal mounting between the link arm and harrow arm. The sleeve bushing also permits relative movement between the half-shafts to accommodate uneven or irregular up and down movement of the harrow arms.
Thus, in both embodiments, the arrangement is such that the link arms of each coil are free to move independently of each other in response to uneven movement of the harrow arms, while at the same time permitting free rotation of the coil about its own longitudinal axis.
Other objects and advantages will become apparent from the detailed description of the preferred exemplary embodiments which follows.